In situ repair of mechanical failure remains a largely unexamined area of study in biomaterials. A newly emerging area of materials science is "Self-Healing Materials" (SHM) that uses a variety of embedded chemistries to detect and repair microcracks in situ before they coalesce into propagating cracks. This R21 proposal examines the feasibility of incorporating biocompatible, non-toxic SHM technology into one of the simplest load-bearing biomaterial formulations -- two component acrylic bone cement -- with the most straightforward SHM technology -- microencapsulated healing agent dispersed in a catalyst-embedded polymer matrix. The study consists of four specific aims. Aim 1: Fabrication of microencapsulated alkyl cyanoacrylate healing agent using emulsified oil in water interfacial polymerization. Aim 2: Incorporation of the icroencapsulated healing agent into the two-component PMMA matrix. Aim 3: Characterization of self-healing bone cement mechanical properties and fracture mechanics. Aim 4: Cytotoxicity testing of self-healing bone cement by elution testing of extraction media in mouse fibroblast culture, and by cell ongrowth onto samples of bone cement placed in cultures of human osteoblasts. PUBLIC HEALTH RELEVANCE: The most likely mode of failure of all cyclically loaded biomaterials is fatigue failure resulting from the accumulation of microcracks. The long-term goal of this study is to develop composite biomaterials that have the capacity to repair failure at the microcrack level and thus prolong the use life of cyclically loaded biomaterials. This project specifically tests out the concept feasibility using acrylic bone cement as a model biomaterial.